(1) Field of the Invention:
This invention relates to fuel systems and fuel gas generators for internal combustion engines.
(2) Description of the Prior Art:
Fuel systems for internal combustion engines have generally used carburetors in which the gasoline is sprayed into a stream of air and divided into a series of fine droplets approaching vaporization and conveyed to the point of combustion by way of the inlet manifold of the engine. Only those molecules at the surface of the gasoline droplets are in a position to react with another species (oxygen) and incomplete combustion results because the very short time allowed is insufficient for more than a little vaporization of the fuel to occur. Internal combustion engines therefore exhaust large quantities of unburned hydrocarbons, carbon monoxide and oxides of nitrogen, all of which are undesirable atomospheric pollutants.
Attempts to improve such fuel systems have included so-called fuel injection systems wherein liquid fuel is injected directly into the inlet manifold of the engine again resulting in only partial vaporization of the fuel although affording improved measurement of the quantities of fuel provided.
Several attempts to improve vaporization through fuel gasification have been made and such devices may be seen in U.S. Pat. Nos. 3,968,775 and 4,112,889 wherein prior devices are disclosed. The devices disclosed in these patents were unable to supply a gaseous fuel to an internal combustion engine under all operating conditions.
Other attempts to produce a gaseous fuel for an internal combustion engine may be seen in U.S. Pat. Nos. 4,023,538, 4,050,419, 4,114,556, 4,145,988, 4,197,819 and 4,333,422.
The inventions disclosed in this group of patents introduce water into the liquid fuel and attempted simultaneous vaporization thereof. Devices formed in accordance with these several patents perform satisfactorily under ideal operating conditions, but were frequently ineffective due to the separation of the liquid fuel vapor and steam into droplets which resulted in incomplete combustion of the fuel mixture and occasional stalling of the internal combustion engines equipped with the devices. Ideal operating conditions for such devices required substantially uniform revolutions per minute or steady miles per hour operation.
This invention relates to a fuel system and vaporizer for an internal combustion engine, the system including a novel fuel gas generator in the form of a double chambered hollow body in one chamber of which liquid fuel, such as gasoline, is introduced. The chamber is maintained at an optimum temperature sufficient to instantly vaporize the liquid fuel by an adjacent heat exchanger, preferably one or more electrically energized resistance heating elements. The hot gaseous fuel produced flows through a valve controlled orifice into the other one of the double chambers in said hollow body, the valve controlling said flow being responsive in operation to inlet manifold pressure in the engine to which the fuel generator is connected. Hot fuel gas flows from said other chamber through an insulated passageway to and through a mechanical valve actuated by the accelerator linkage controlling said engine and into the inlet manifold thereof by way of an adaptor plate on which the usual carburetor is mounted. The butterfly valve of the carburetor is actuated by the same accelerator linkage. Water vapor as superheated steam from a suitable source is introduced into the carburetor below the butterfly valve and mixes with the hot fuel gas directed into the inlet manifold. The superheated steam is generated in a separate combination control valve and heat exchanger, the control valve being responsive in operation to the revolutions per minute of the engine and the heat exchanger preferably an electrically energized resistance heating element.